ETMOPTERUS BRACHYURUS. 227 



one third of the distance from the caudal; origin above the axils of the ventrals. 

 Ventrals reaching little behind the spine of the second dorsal. Caudal two 

 sevenths of the total length, separated at the terminal by a shallow notch, 

 lower angle hardly developed, broadly rounded. Scales with short setiform spines 

 arranged in more or less regularly longitudinal series on the upper surfaces, the 

 flanks, and below the tail, everywhere except in the heavily pigmented areas of 

 black on the lower surface and lower part of the flank near the base of the tail. 

 In the black areas, the outlines of which somewhat closely agree with those of 

 E. hillianus, Plate 10, fig. 1, the spines appear evenly distributed. 



Back and flanks blackish brown, the brown separated from the black of the 

 lower surfaces by longitudinal bands of whitish, probably becoming uniform 

 black with age. Young specimens much lighter. In the specimens described 

 the markings are closely similar to those of E. hillianus and E. spinax: there is a 

 whitish spot on the forehead, another behind each orbit, an oblique band from 

 the forward gill opening, a longitudinal from above and behind each pectoral 

 along the flank at the edge of the black to a point above the base of the ventral 

 where a branch is sent in front of the pelvis while the band ends behind the fin 

 against a dark area which passes up to the flank and extends a narrowing band 

 forward above the ventral and backward below the second dorsal; except in the 

 basal portions and in the end of the tail the fins are light. 



Total length of an adult male II5, snout to vent 6, snout to dorsal spine 3|, 

 snout to pectoral 2|, snout to mouth l|, and caudal 2| inches. 



Odawara, Japan. 



EtMOPTERUS BRACHYURUS. 



Elmo-pterus brachyurus Smith & Radcliffe, 1912, Proc. U. S. nat. mus., 41, p. 679, fig. 2, pi. 52. 



Distinguished from Etmopterus lucifer by the much shorter caudal fins and 

 by the origin of the second dorsal, which is behind the tips instead of above the 

 axils of the ventral fins. Lines of sharp spines appear on both species. The 

 head of E. brachyurus is broader, the mouth wider and the snout shorter than 

 in E. lucifer. Width of mouth and length of snout {i. e. distance from mouth 

 to end of snout) about equal. Snout broad, depressed. Origins of the ventrals 

 little behind midway from the origin of the first dorsal to that of the second. 

 Origin of the first dorsal above the ends of the pectorals. Nostrils large, near 

 the end of the snout, internarial space wider. Upper teeth small, five-cusped. 

 Lower teeth larger, one-cusped, cutting edge rising obhquely outward. Spiracles 

 rather large, near midway from the end of the snout to the hindmost gill opening. 



